I want to start sharing a bit more educationally-focused information here. However, in line with my long history of utilizing social media to connect with patients and understand the human side of the story, I hope to employ my non-medical, digital-friends to inspire these topics.

Hannah from Daytrips & Diapers has graciously given me permission to discuss/link her in this post. She is pregnant with monochorionic – diamniotic twins and was diagnosed with twin-twin transfusion syndrome (TTTS) at 16 weeks. She recently traveled to the nearest fetal surgery center, >8 hours from her home, and underwent a procedure aimed at decreasing placental connections and improving blood flow (and hopefully, outcomes) for both babies.

She then experienced a known complication of the surgery, however at the time of my writing is still joyfully pregnant with both of her twins. Hop over to her blog or Instagram and follow her story for the human side of medicine. Read on below if you’re interested in the medical side – I’ll discuss diagnosis, pathophysiology, and treatment of TTTS below.

What is Twin-Twin-Transfusion Syndrome?

A complication isolated to monochorionic (one placenta) twin pregnancies where vascular connections on the shared placenta develop pressure/flow gradients. This allows one twin (“donor”) to become anemic and the other (“recipient”) to become plethoric and begins a cascade of physiologic changes which can become catastrophic.

How Often Does This Occur?

The incidence in mo/di pregnancies is about 10-15% and bout 6% in mo/mo twins develop TTTS. Dichorionic twins cannot develop twin-twin transfusion syndrome, as they have two placentas.

How Is Twin Twin Transfusion Syndrome Diagnosed?

The diagnosis is made clinically by ultrasound. It is classically identified by “Poly-Oli Sequence”

!! This will be how it’s presented on USMLE-type exams. !!

Refers to polyhydramnios of recipient twin and oligohydramnios of donor twin.

Occasionally, there will be such severe oligo in the donor twin that it develops “Stuck Twin,” which is essentially the ultrasound appearance of a donor twin being stuck to the placenta. Anatomically, this results from such severe oligohydramnios that the amniotic sac is lying directly against the fetus.

They are daunting, for sure. However, TTTS severe enough to warrant laser-intervention which is left completely un-treated will result in fetal death of one twin in nearly 100% cases and both twins in >90%. These outcomes, when appropriate candidates are selected, are far superior to no treatment.

That’s a brief overview of TTTS and fetoscopic laser ablation. I’ve done a few LIVE Q&As on Twins, I’ll try to round those up to get on YouTube for a more thorough discussion of the pathophysiology and also the different types of twins.

It’s so important when learning about things like this that we don’t forget there’s a human (or, in this case 3) on the other side of our text books. Hop over to the blog and/or IG linked in the intro paragraph for a view into how this looks from a patient perspective.

Danielle Jones, MD

Disclosure: I share links to products that I genuinely believe in so you can easily find them. Some of these links are affiliate links, which let you support me on my blogging endeavors. To read more, see my affiliate disclosure here.

MamaDoctorJones on Instagram

Load More

Something is wrong. Response takes too long or there is JS error. Press Ctrl+Shift+J or Cmd+Shift+J on a Mac.

Amazon Affiliate

This site contains Amazon affiliate links. MamaDoctorJones may receive compensation (at no extra cost to you) if you like or purchase something she links to! She only shares products she truly believes in.